Drawing instrument.



J. DZIERWA.

DRAWING INSTRUMENT.

APPLIUATION IILED JUNE 5, 1911.

' 1,021,583. Patented Mar.26, 1912.

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DRAWING INSTRUMENT. "APPLIOATION FILED 1111135, 1911.

1,021,583. Patented Mar. 26, 1912.

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DRAWING INSTRUMENT.

APPLICATION II/LBD JUNE 5, 19 11.

' Patented Mar. 26, 1912.

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fiHfliiillllllllllllllllllllllllllllllll|||III|||I||||||ll||IIIIIIIIIIIIIII||||I A 7i 5 7 v a" e 1 FTEFE N IE1 LJlll UNITED STATES PATENT OFFICE.

JOHN DZIERWA, OF ST. LOUIS, MISSOURI.

DRAWING INSTRUMENT.

To all whom "it may concern:

Be it known that'I, JOHN DziiiRwA, a citizen of the United States,residing in the city of St. Louis and State of Missouri, have inventedcertain new and useful Improvements in Drawing Instruments; and I do:declare the following to be a full, clear, and

exact description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

This invention relates to drawing instruments, more particularly of thatcharacter which are intended for drawing ellipses, ovals, circles, andthe like; and the object of the same is to produce an instrument thatcan be so used and wherein all parts, excepting an ordinary yardstick orthe like, may be folded into small compass. This object is accomplishedby the construction hereinafter more fully described and claimed and asshown in the drawings wherein:

Figure 1 is a top plan view showing the manner in which the device isemployed; Fig. 2 is a side view of the invention; Fig. 3 is a similarview of the beam detached; Fig. 4 is a verticalsectional view of one ofthe posts, showing more particularly the pin fastening means thereof;Fig. 5 is a horizontal sectional view on line 5-5 of Fig. 4; Fig. 6 is aview of the several parts of the mechanism for adjustably securing theposts to the beam; Fig. 7 is a top plan view of the cross member in afolded position; Fig. 8 is an enlarged side view of a portion thereof;Fig. 9 is a vertical sectional view on line 99 of Fig. 8; Fig. 10

is a detail perspective view of one of the supporting and retainingfeet.

8 alternately disposed with catches which latter comprise each a member9 secured to one side of the arm opposite the hinge 8 and having anoutstanding rib 10 and a member 11 secured to the same side of theadjacent arm and having a hook 12 at its free end adapted to engage saidrib when the two sections of the arm stand in alinement as Specificationof Letters Patent.

Application filed June 5, 1911.

Patented Mar. 26, 1912.

Serial No. 631,213.

seen in the drawings. In order to prevent this cross from slipping overthe pap-er or board upon which the drawing is to be made, it is providedwith feet 13 on its under side as best seen in Fig. 8, and these feetare by preference repeated at the outer end of each section of each arm.hinges and catches are by preference of metal, whereas the arms of thecross and its rigid center may all be of wood; and of course the exactshape, the proportions, and the sizes of parts are immaterial. The otherelement of this instrument is made up of a ruler which may well be ayardstick as lettered Y herein, and three elements or members which Iwill now specifically describe.

These and the- Each-has an upright body 20 provided across its upper endwith a transverse slot 21 of a size to receive the ruler or yardstick Y;and the solid member or guide member 30 has the remainder of its bodymade solid and a pin 31 projecting from its lower end and of a size toslide freely within the groove 6. One member has a spring actuated catch42 for holding a steel point 43 whose body is grooved as at 44 so thatthe catch may engage it at different heights and permit the point properto project to different degrees. The lower end of this mem- V ber is bypreference formed with a pin 41, similar to the pin 31 except that it istubular to permit the steel point to pass through it; and when thispoint is removed the two pins 31 and 41 serve as guides in a nannerwhich will be described below. The third member has a spring catch 52much like that nuin' bered 42.exceptthat it is shaped to engage the bodyof a pencil 53 which also may be set under this catch so as to projectto greater or less extent as desired; and this member omits the pin atthe lower end of at the upper ends of all these three members are alike,and a description of one will suffice for all. levers 60 having sideears 61 pivoted as at 62 to the upper end of the fork of the member ateach side of its slot 21, the lower ends of said levers bearing upon ashoe 63 which slides along the upper edge of the yardstick Y, and theirupper ends forming thumbpieces which may be compressed between the thumband finger of the operators hand. The inner faces of said thumb-piecesare socket-ed as 65 to receive the extremities of an expansive coiledspring 66 which nor- Each comprises two L-shaped iie mally throws themapart and depresses the shoe so as to frictionally bind upon the upperedge of the yardstick and therefore hold this member in adjustedposition. When it is desired to move it along the same, the thumb piecesare pressed together against the tension of this spring and the wholemember can then be moved and set as desired, after which the pressure isrelieved and the expansion of the spring holds the member so adjusted.

In the use of this device for drawing plain pencil circles, the steelpoint is 1nserted in the member 40 and the pencil in the member 20, andthe said pencil is swung around the center in a manner which will beclear, the tips of both the point and the pencil projecting below thepin 31 at the lower end of the member 30. Or the point may be insertedin the hole 7 at the center of the cross, and the pencil will travelaround upon the paper or board between its arms and must be lifted overthem as they are encountered. To draw or scratch lines upon wood ormetal, a metal point or pin is substituted for the pencil and theoperation is the same. WVhen this instrument is used to draw ovals, thepoint is removed from the member 40 and the two pins 4L1 and 31 areseated in the grooves 6 with the pencil depending from the third member,and then the entire yardstick Y is swung around by the operators handwhich grasps the pencil and the member which carries it, one pin movingalong the groove in two alined arms and across the center, then theother pin moving inward in a direction at right angles thereto andacross the center, then the first pin returning across the center, andso on in a manner which will be clear. VVhet-her drawing circles orovals, all the members are set on the yardstick by the means abovedescribed, according to the size of the oval or circle that is to bestruck. hen this device is not in use the members are removed from theyardstick and the arms of the cross are folded up into small compass asshown.

\Vhat is claimed as new is:

1. In a drawing instrument of the class described, the combination witha stick, members adjustably mounted thereon and two of them having pinsat their lower ends, and a marking device carried by the third; of across comprising a rigid center, foldable arms comprising sectionshinged to the outer ends of the arms of said center, the hinges betweenthe sections of the foldable arms being alternately on opposite sides ofsaid arms, and catches disposed opposite the hinges, the upper edges ofsaid arms and sections being grooved for the reception of said pins.

2. In a drawing instrument of the class described, the combination witha stick, members adjustably mounted thereon, and two of them having pinsat their lower ends, and a marking device carried by the third;

:of a cross comprising a rlgid center, foldable arms comprising sectionsat the outer extremities of the arms of said center, a. hinge at oneside of each joint between said arms, and a catch at the other side ofsuch joint comprising one member having an out-turned rib and anothermember having an inturned hook adapted to engage the rib when the partsare in alinement, all arms having grooves in their upper edges adaptedfor the reception of said pins.

3. In a drawing instrument of the class described, the combination witha stick, members adjustably mounted thereon and two of them having pinsat their lower ends, and a marking device carried by the third; of across comprising a rigid center, foldable arms comprising sections atthe outer extremities of the arms of said center, a hinge at one side ofeach joint between said arms, a catch at the other side of each suchjoint comprising one member having an out-turned rib and another memberhaving an inturned hook adapted to engage the rib when the parts are inalinement, all arms having grooves in their upper edges adapted for thereception of said pins, and feet depending from the lower edges of thecenter and of each of said sections.

4. In a drawing instrument of the type described, the combination with astick, and members thereon each having a transverse slot through itsupper end adapted to re celve said stick; of brackets at opposite sidesof the slot in each member, two L- shaped levers having knuckles attheir angles lapping each other and standing between said brackets, apivot pin through the brackets and knuckles, an expansive spring betweenthe upper ends of said levers, and a shoe beneath their lower endsadapted to bear upon said stick.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

JOHN DZIERIVA.

W'itnesses:

JOHN A. ANDERSON, LOUIS E. RoBER'rs.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, I). 0.

